It is known to provide a gripper device or manipulator for receptacles such as bottles having necks engageable in individual grippers of the manipulator where the number of grippers mounted in the gripper head or manipulator head is equal to the number of bottles to be inserted simultaneously into a box or other container or to be withdrawn from a box or other container.
The grippers can have hollow cylindrical sockets into which the neck of the bottle can be introduced and an elastic insert which can be axially compressible by a piston to enable the elastic insert to grip or release the neck of the bottle.
The individual grippers or their elastic inserts have configurations similar to that of a tulip and can be referred to as packing tulips or tulip elements.
A gripper system of this type is described in German patent 38 19 598 and has been found to be highly satisfactory. However, the individual grippers of this system have a cylindrical outer configuration and, because the socket itself must have a certain minimum diameter, the cylindrical configuration limits the center to center spacing of the sockets and hence the center to center spacing of the receptacles or bottles which are to be handled. In other words, in many cases, this type of gripper arrangement could not have the center to center spacing of the containers in a box.
As a result, especially with bottles whose neck diameters are only slightly smaller than the body diameters, gripper systems of this type could not be used. As a more general matter, whenever the diameters of the grippers were such that the center to center spacing exceeded center-to-center spacing of the bottles in the package to be formed or from which the bottles were to be withdrawn, the system could not be used either.